Endospore normally repels stains used to visualize bacteria. What does that imply about the structure regarding its sensitivity to other harsh chemicals, like antibiotics and disinfectants?
- Its hard to kill
- It is has a strong ability to repel antibiotics and disinfectants
What is malachite green used for?
How is it forced into an endospore?
What is malachite green used for?
- Endospore staining
How is forced into an endospore?
- Heat, we used the heat from steam
What genera produce endospores?
Clostridium
Bacillus
What conditions result in the formation of endospores?
- Nutrient-poor environments
When viewing cells via a simple stain or a Gram stain, what other structures might be confused with endospores ? Give at least two examples.
- Granules
- Gas Vesicles
What is the purpose of negative staining?
- See capsules around a bacteria by staining background of cells and not cells or capsules themselves
- Capsules stay intact
- No heat fixation needed
How are dyes with negative charges related to the predominant charges on the surface of cells?
- Surface of cells -> (-) charged
- Dye and Cells and are repelled electrostatically, so the dye stains the background
Why is sodium thioglycollate or cysteine needed for the survival of certain prokaryotes?
They reduce O2 to H2O, and anaerobes cannot handle the presence of O2
What are two enzymes that enable prokaryotes to “handle” oxygen?
- Superoxide dismutase
- catalase
